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Index exceeds the number of array elements (1).

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Heya :)
Heya :) on 25 Nov 2020
Commented: Heya :) on 25 Nov 2020
I am unable to spot why I am getting an error. Please help to resolve the error.
x1_rec(1)=x1(1);
x2_rec(1)=x2(1);
y1_rec(1)=y1(1);
y2_rec(1)=y2(1);
%value of constants
%a1=x1
a1=ksaix1(1);
a2=ksaix1(2);
a3=ksaix1(3);
a4=ksaix1(4);
a5=ksaix1(5);
a6=ksaix1(6);
a7=ksaix1(7);
a8=ksaix1(8);
a9=ksaix1(9);
a10=ksaix1(10);
a11=ksaix1(11);
a12=ksaix1(12);
a13=ksaix1(13);
a14=ksaix1(14);
a15=ksaix1(15);
a16=ksaix1(16);
a17=ksaix1(17);
a18=ksaix1(18);
a19=ksaix1(19);
a20=ksaix1(20);
a21=ksaix1(21);
a22=ksaix1(22);
a23=ksaix1(23);
a24=ksaix1(24);
a25=ksaix1(25);
a26=ksaix1(26);
a27=ksaix1(27);
a28=ksaix1(28);
a29=ksaix1(29);
a30=ksaix1(30);
a31=ksaix1(31);
a32=ksaix1(32);
%c=x2
c1=ksaix2(1);
c2=ksaix2(2);
c3=ksaix2(3);
c4=ksaix2(4);
c5=ksaix2(5);
c6=ksaix2(6);
c7=ksaix2(7);
c8=ksaix2(8);
c9=ksaix2(9);
c10=ksaix2(10);
c11=ksaix2(11);
c12=ksaix2(12);
c13=ksaix2(13);
c14=ksaix2(14);
c15=ksaix2(15);
c16=ksaix2(16);
c17=ksaix2(17);
c18=ksaix2(18);
c19=ksaix2(19);
c20=ksaix2(20);
c21=ksaix2(21);
c22=ksaix2(22);
c23=ksaix2(23);
c24=ksaix2(24);
c25=ksaix2(25);
c26=ksaix2(26);
c27=ksaix2(27);
c28=ksaix2(28);
c29=ksaix2(29);
c30=ksaix2(30);
c31=ksaix2(31);
c32=ksaix2(32);
h=0.1; %step size
t=0:h:50;
%ode
p=@(t,x1_rec,y1_rec,x2_rec,y2_rec) a1+a2*x1_rec+a3*x2_rec+a4*y1_rec+a5*y2_rec+a6*x1_rec*x2_rec+a7*y1_rec*y2_rec+a8*x1_rec*y1_rec+a9*x1_rec*y2_rec+a10*x2_rec*y1_rec+a11*x2_rec*y2_rec+a12*x1_rec*x2_rec*y1_rec+a13*x1_rec*x2_rec*y2_rec+a14*x1_rec*y1_rec*y2_rec+a15*x2_rec*y1_rec*y2_rec+a16*x1_rec*x2_rec*y1_rec*y2_rec+a17*x1_rec^2+a18*x2_rec^2+a19*y1_rec^2+a20*y2_rec^2+a21*x1_rec^2*x2_rec+a22*x1_rec^2*y1_rec+a23*x1_rec^2*y2_rec+a24*x2_rec^2*x1_rec+a25*x2_rec^2*y1_rec+a26*x2_rec^2*y2_rec+a27*y1_rec^2*x1_rec+a28*y1_rec^2*x2_rec+a29*y1_rec^2*y2_rec+a30*y2_rec^2*x1_rec+a31*y2_rec^2*x2_rec+a32*y2_rec^2*y1_rec;
q=@(t,x1_rec,y1_rec,x2_rec,y2_rec) c1+c2*x1_rec+c3*x2_rec+c4*y1_rec+c5*y2_rec+c6*x1_rec*x2_rec+c7*y1_rec*y2_rec+c8*x1_rec*y1_rec+c9*x1_rec*y2_rec+c10*x2_rec*y1_rec+c11*x2_rec*y2_rec+c12*x1_rec*x2_rec*y1_rec+c13*x1_rec*x2_rec*y2_rec+c14*x1_rec*y1_rec*y2_rec+c15*x2_rec*y1_rec*y2_rec+c16*x1_rec*x2_rec*y1_rec*y2_rec+c17*x1_rec^2+c18*x2_rec^2+c19*y1_rec^2+c20*y2_rec^2+c21*x1_rec^2*x2_rec+c22*x1_rec^2*y1_rec+c23*x1_rec^2*y2_rec+c24*x2_rec^2*x1_rec+c25*x2_rec^2*y1_rec+c26*x2_rec^2*y2_rec+c27*y1_rec^2*x1_rec+c28*y1_rec^2*x2_rec+c29*y1_rec^2*y2_rec+c30*y2_rec^2*x1_rec+c31*y2_rec^2*x2_rec+c32*y2_rec^2*y1_rec;
%loop
for i=1:(length(t)-1)
k1=p(t(i),x1_rec(i),y1_rec(i),x2_rec(i),y2_rec(i));
l1=q(t(i),x1_rec(i),y1_rec(i),x2_rec(i),y2_rec(i));
k2=p(t(i)+h/2,(x1_rec(i)+(h/2)*k1),(y1_rec(i)+(h/2)*l1),(x2_rec(i)+(h/2)*k1),(y2_rec(i)+(h/2)*l1));
l2=q(t(i)+h/2,(x1_rec(i)+(h/2)*k1),(y1_rec(i)+(h/2)*l1),(x2_rec(i)+(h/2)*k1),(y2_rec(i)+(h/2)*l1));
k3=p(t(i)+h/2,(x1_rec(i)+(h/2)*k2),(y1_rec(i)+(h/2)*l2),(x2_rec(i)+(h/2)*k2),(y2_rec(i)+(h/2)*l2));
l3=q(t(i)+h/2,(x1_rec(i)+(h/2)*k2),(y1_rec(i)+(h/2)*l2),(x2_rec(i)+(h/2)*k2),(y2_rec(i)+(h/2)*l2));
k4=p(t(i)+h,(x1_rec(i)+k3*h),(y1_rec(i)+l3*h),(x2_rec(i)+k3*h),(y2_rec(i)+l3*h));
l4=q(t(i)+h,(x1_rec(i)+k3*h),(y1_rec(i)+l3*h),(x2_rec(i)+k3*h),(y2_rec(i)+l3*h));
x1_rec(i+1) = x1_rec(i) + h*(k1+2*k2+2*k3+k4)/6;
%y1(i+1) = y1(i) + h*(l1+2*l2+2*l3+l4)/6;
x2_rec(i+1) = x2_rec(i) + h*(k1+2*k2+2*k3+k4)/6;
%y2(i+1) = y2(i) + h*(l1+2*l2+2*l3+l4)/6;
end
plot(x1_rec(1:length(x1)),'r','LineWidth',2)
plot(x2_rec(1:length(x2)),'r','LineWidth',2)
%%%%%Error%%%%
Index exceeds the number of array elements (1).
Error in coup (line 333)
k1=p(t(i),x1_rec(i),y1_rec(i),x2_rec(i),y2_rec(i));

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Answers (2)

KSSV
KSSV on 25 Nov 2020
The error is clear...you are trying to extract more number of elements than present int he array.
A = rand(1,10) ;
A(1) % no error
A(5) % no error
A(end) % no error
A(11) % error, as there is no 11th element
Your code is very long and also you are accessing some local data in between which we don't have access to. So we cannot help you exact on the point. But the error occurs due to the reason mentioned above.

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Heya :)
Heya :) on 25 Nov 2020
Is their a way to change the size of x1_rec, y1_rec, x2_rec, y2_rec?
x1_rec(1)=x1(1);
x2_rec(1)=x2(1);
y1_rec(1)=y1(1);
y2_rec(1)=y2(1);
KSSV
KSSV on 25 Nov 2020
You have messed up with your code at lot of places.
Heya :)
Heya :) on 25 Nov 2020
That is why i am here asking for help

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Nora Khaled
Nora Khaled on 25 Nov 2020
can't run your code because it need to open file.
But check the sizes x1_rec, y1_rec, x2_rec, and y2_rec.
it seems that you the for loop exceed the number of elements.

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Show 5 older comments
Heya :)
Heya :) on 25 Nov 2020
Yes you are right. How to adjust the size?
KSSV
KSSV on 25 Nov 2020
so use linspace:
t = linspace(0,50,50) ;
Or run the loop index upto length of t.
Heya :)
Heya :) on 25 Nov 2020
You mean this for i=1:(length(t))?

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